ES6的getter和setter用法

set __proto__和get __proto__是Object原型链的方法，设置访问器要重写此方法

image.png

语法

get [属性名]{}
get [属性名]{}

const language = {
  current: "javascript",
  lang: "javascript",
  get current() {
    // return 12;
  },
  set current(lang) {
    // this.current = lang; //递归了堆栈溢出
    this.lang = lang;
  },
};
console.log(language);
language.current = "go";
console.log(language); //go
console.log(language.current); //undefined
class Lang {
  language = "javascript";
  get language() {
    console.log("get");
    return "java";
  }
  set language(lang) {
    this.lang = lang;
  }
}
const l = new Lang();
console.log((l.language = 4));
console.log(l); //{language:4}

getter

访问属性的时候调用此方法,不能设置形参， 否则报错，有返回值

setter

设置属性的时候调用此方法,不能设置形参，否则报错